In　this　article,　we　developed　an　electrochemiluminescence　(ECL)　sensor　with　a　high-intensity　charge　transfer　interface　for　Hg2+　detection　based　on　Hg(II)-induced　DNA　hybridization.　The　sensor　was　fabricated　by　the　following　simple　method.　First,　graphene　oxide　(GO)　was　electrochemically　reduced　onto　a　glassy　carbon　electrode　through　cyclic　voltammetry.　Then,　amino-labeled　double-stranded　(ds)DNA　was　assembled　on　the　electrode　surface　using　1-pyrenebutyric　acid　N-hydroxysuccinimide　as　a　linker　between　GO　and　DNA.　The　other　terminal　of　dsDNA,　which　was　labeled　with　biotin,　was　linked　to　CdSe　quantum　dots　via　biotin-avidin　interactions.　Reduced　graphene　oxide　has　excellent　electrical　conductivity.　dsDNA　with　T-Hg(II)-T　base　pairs　exhibited　more　facile　charge　transfer.　They　both　accelerate　the　electron　transfer　performance　and　sensitivity　of　the　sensor.　The　increased　ECL　signals　were　logarithmically　linear　with　the　concentration　of　Hg(II)　when　Hg2+　was　present　in　the　detection　solution.　The　linear　range　of　the　sensor　was　10(-11)　to　10(-8)　mol/L　(R=0.9819)　with　a　detection　limit　of　10(-11)　mol/L.　This　biosensor　exhibited　satisfactory　results　when　it　was　used　to　detect　Hg(II)　in　real　water　samples.　The　biosensor　with　high-intense　charge　transfer　performance　is　a　prospect　avenue　to　pursue　more　and　more　sensitive　detection　method.　(C)　2015　Elsevier　B.V.　All　rights　reserved.